How to Flash a zImage Kernel for the Sprint Galaxy S2 (SPH-D710)
(Updated 08/23/2012)

These instructions are specific to the Sprint Galaxy S2 (Epic 4G Touch or SPH-D710).   Although similar methods may work with other phones this method uses methods that ARE NOT compatible with any other phone but the Sprint Galaxy S2.   If you do not have the Sprint Galaxy S2 please DO NOT follow these instructions as they will most likely brick your phone!

Prerequisites
  • Your device must be rooted. If it is not rooted please see the How To Root tutorial here.
  • You'll need to have the zImage file saved to your phone.
    zImage files can only be flashed with Mobile Odin.  zImage files MUST be named zImage or they will not flash properly. I recommend keeping them in seperate folders to identify which kernel you are flashing.
  • You must have Mobile Odin installed on your device.
    Mobile Odin Pro can be purchased from the Market or there is a free XDA version for XDA members. I'd suggest the Market Pro version - it has additional features and all proceeds go to supporting Chainfire who is an awesome developer! If you prefer the free version you can find it here.
Instructions
  1. Open Mobile Odin.
  2. Select "Open File".
  3. Select either "Internal SD-card" or "External SD-card" (depending on where you saved the zImage update file you previously downloaded).
  4. Browse to the zImage update file.
  5. Select "Flash firmware".
  6. Select "Continue".
  7. If prompted select "Check" to verify the MD5 signature.
    Your phone will now reboot (if you phone does not reboot within 30 seconds you should inititiate the reboot yourself by pressing and holding the power button).  This reboot take slightly longer than usual.  Depending on the kernel you are flashing there may or may not be a boot animation, please be patient while your phone reboots.
    After your phone has fully booted you may see a message saying "Android is upgrading.  Optimizing application ## of ###" Where ## is the app number it is currently optimizing and ### is the total number of apps you have on your phone.
Congratulations! You are now running your new kernel!

If you have additional questions or would like to discuss these methods further please visit the Rwilco12 Android Forums.